Regulating Strategy And Effect Evaluation Of Inverter Air-Conditioner Applied In Demand Response

In recent years, air-conditioning load has become the most significant reason of the peak load rising, which brings great negative impact on the operation of power grid. While through the reasonable control measures (such as changing setting temperature, start-stop control, etc.), Air-conditioning load can be helpful in reducing the peak power demand and improving the efficiency of the system without affecting the users' comfort degree. Currently, load control techniques of ordinary air conditioner and central air conditioner have successful research and practice in some developed countries. However, inverter air-conditioner becomes the mainstream of domestic air-conditioning market now. The existing load model and control measure are no longer applicable for it, which cannot meet the needs of the electricity market in the future.This paper first analyze the load characteristics of inverter air-conditioner and establish a single air-conditioning load model on the basis of the first-order equivalent thermal parameters model. Strategies for inverter air-conditioner group in peak regulation and frequency modulation of power grid are proposed based on human comfort degree. Finally, the paper discusses the effect evaluation methods of inverter air conditioner in the demand response.Firstly, on the basis of extensive reading the domestic and foreign literatures, the common air-conditioner control technology in demand response is summarized, which includes air-conditioner circumstance load modeling, load control methods in power regulation and effect evaluation in demand response. Besides, present application of air conditioning load control at home and abroad is introduced.Secondly, based on the load characteristics of inverter air-conditioner, the function between room temperature and compressor frequency is formed with equivalent thermal parameters (ETP) model and fitting function between compressor frequency and cooling capacity. After single inverter air-conditioner load modeling, the paper discussed the feasibility for inverter air-conditioner participating in power system regulation.Thirdly, the paper study the capability for inverter air conditioner groups in demand response by the premise of meeting human comfort; on this basis, a double-layer load control strategy of inverter air-conditioner groups is proposed. Genetic algorithm is used to optimize the control temperature or compressor frequency in order to meet the grid scheduling deviation while minimizing the user's comfort degree.Furthermore, the technical framework for inverter air conditioner group involved in frequency modulation is proposed. After determining the parameters for inverter air conditioner automatic modulating frequency, the paper put forward a secondary frequency regulation method, which the load aggregators are set as the intermediate. The single-area power model including inverter air conditioner group proved that the method improved the frequency characteristics of power grid indeed.Finally, the paper establish the model for verifying the effect of air conditioning load in demand response project. Based on the indoor and outdoor temperature difference, a baseline computation method with regression analysis for inverter air-conditioner is formed. The computation method is available for quantify and evaluate the demand response effect for air-conditioners, which is more accurate than traditional baseline computation method in dynamic calculation.